Hexabranchus sanguineus (Rüppell & Leuckart, 1830) [Doris]

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Hexabranchus sanguineus is very variable in colour. At the Philippines is this mottled variant most common. It is able to swim and is one of the largest nudibranchs. I have seen 3 specimens pretty deep at "Sunken Island", off Cebu Island which had at least 40 cm, they reached from my elbow to the finger-tips. At first sight I thought the gills are a bunch of algae. There is no picture of them, I was still working with the legendary NIKONOS-V, using 2-close-up sets for real macro shots (even only one of the 6 gills was very much too large). Shit happens, my dive buddy Klaus Stark had forgotten to replace the film in his camera...
Michael D. Miller has at his Slug Site some pictures of the "Giant Spanish Dancers" taken by David Mulliner as Opisthobranch of the week June 1998, Those specimens were reported from Pescador Island, off Moalboal, Cebu at 140 ft (~43 m) depth, their size was nearly two (2) feet (~50 cm),
picture #10 (posted on 16 June 2016) was taken at the at the same location, this specimen was more than 40 cm long.
When disturbed it unrolls its wide mantle skirt, here starting to unroll here it is unrolled.
I have posted more pictures of Hexabranchus sanguineus than usal, (I started these websites with max. 5 pictures of each species) because I wanted to show this juvenile specimen, this almost adult (3,5 - 4 cm) specimen, this swimming specimen, and this specimen showing the oral tentacles.
This species was published on 18 June 2003 on these websites as Hexabranchus sanguineus (Rüppell & Leuckart, 1828) [Doris],
I know since a few days that Rüppell & Leuckart (1828 - 1830) is online, see reference. This text was published in 2 parts,
the pages 1 - 22 in 1828, and the pages 23 - 47 in 1830. Doris sanguinea appears on page/Seite 28 and on plate/Tafel VIII,
that is the year must be 1830.
I changed it on 10 January 2016 into Hexabranchus sanguineus (Rüppell & Leuckart, 1830) [Doris].
Rüppell E. & Leuckart F.S. (1828-1830). Mollusca [in] Atlas zu der Reise im nördlichen Afrika von Eduard Rüppell. 1. Abth. Zoologie. 5. Neue wirbellose Thiere des Rothen Meers.
Frankfurt, H.L. Brönner pp. 1-22, pl. 1-12 [1828], pp. 23-47 [probably 1830], page(s): 28, plate VIII, Figure 1
available online at http://www.biodiversitylibrary.org/item/114235#page/349/mode/1up.
More information on Hexabranchus sanguineus are on Bill Rudman's Sea-Slug Forum!
How to cite:
Köhler, E. (2016), published 14 November 2016, Hexabranchus sanguineus (Rüppell & Leuckart, 1830)
available from https://www.Philippine-Sea-Slugs.com/Nudibranchia/Euctenidiacea/Hexabranchus_sanguineus.htm